Histology

Question 1

Thyroid - hormone info

Answer 1

• TH-major metabolic hormone & is released in blood by elevated TSH levels
• TH- T3+T4–needs iodine to be activated
• T4 –thyroxine (med for hyperthyroidism)
• T3–active form & T4 is converted to T3 when active

Question 2

TSH

Answer 2

A fat soluble H-so it needs a carrier protein for blood transport-TBG

Question 3

TBG

Answer 3

Thyroid binding globulin

Question 4

parafollicular cells

Answer 4

• produce H called calcitonin (calcium)
• inhibits osteoclasts and stimulates osteoblasts–lowers Ca++ when Ca++ level is high
• released by high Ca++ levels–decrease blood Ca++
• impact with kids

Question 5

Parathyroid gland

Answer 5

• Ca++ homeostasis –PTH–increase osteoclast activity (break down bone to release Ca++ into body) – increase Ca++
• humoral release
• osteoporosis could mean PTH levels high
• most important for adult Ca++ homeostasis

Question 6

Chief cells

Answer 6

in parathyroid glands
principal cells=parathyroid cells
not much cytoplasm
stain dark blue
more abundant than oxyphil

Question 7

oxyphil cells

Answer 7

• unknown function
• in parathyroid glands
• a lot more cytoplasm than a chief cell

Question 8

Adrenal (suprarenal) gland

Answer 8

• located in the fat above each kidney
• very vascular
• adrenal cortex (3 layers)
• adrenal medulla

Question 9

adrenal cortex

Answer 9

• zona glomerulosa
• zona fasciculata
• zona reticularis

Question 10

zona glomerulosa hormone

Answer 10

• aldosterone –cause kidneys to retain Na+ and excrete K+
• stimulus for release is elevated K+
• ACTH is not impact for aldosterone release

Question 11

zona fasciculata- hormone info

Answer 11

• cortisol (hydrocortisone)–makes new glucose from fats & proteins (amino acids)
• cortisol in excess is anti-inflammatory & anti-immune
• RH arthritis flare, transplants–prednesone (form of cortisol)

Question 12

zona reticularis - hormone info

Answer 12

• weak androgens–male & female hormones

* at target tissue they are converted to testosterone & estrogen

Question 13

andrenal medulla

Answer 13

• catecholamines

* 75% E (metabolism) and 25% NE (vasoconstrictor)

Question 14

Pancreas

Answer 14

• pancreatic islets (Langerhan’s) are the endocrine part
• alpha cells
• beta cells
• negative feedback balancing act

Question 15

alpha cells

Answer 15

• pancreas
• reddish/pinkish
• release glucagon which increases blood glucose
• targets liver primarily–glycogen (stored form) break down & glucose into blood stream ex: hypoglycemia; sleeping

Question 16

beta cells

Answer 16

• pancreas
• bluish
• produce insulin which decreases blood glucose
• insulin is a 51 amino acid protein that affects almost all of our cells

Question 17

Pineal gland

Answer 17

• melatonin

* antigonadotropic

Question 18

thymus hormone info

Answer 18

• thymic H–responsible for differentiation of WBC called lymphocyte–T cell lymphocyte
• big player in immune system

Question 19

erythrocyte

Answer 19

• RBC
• biconcave disc
• no nucleus
• carry Hb
• about 44-45% of whole blood volume

Question 20

Hemoglobin

Answer 20

• Hb
• consists of 4 hemes (contain iron in each) plus 1 globin
• function is to carry or transport O2
• each Hb carries a max of 4 O2 molecules
• can also transport CO2

Question 21

leukocytes

Answer 21

granulocytes: neutrophils; eosinophils; basophils
agranulocytes: lymphocytes; monocytes

Question 22

neutrophils

Answer 22

• most numerous
• faint granules
• nucleus has 3-6 lobes; multilobed
• phagocytes: associated with acute bacterial infection
• Granules: enzymes & antibiotic like proteins called defensins
• bigger than lymphocyte; nucleus is very odd; granules don’t take up stain

Question 23

eosinophils

Answer 23

• 1-4%
• dark red granules
• nucleus has 2 lobes
• granules: enzymes that kill parasitic worms
• contribute to tissue damage
• Larger; granules take up stain

Question 24

basophils

Answer 24

• .5%
• blue/black granules: contain histamin & heparin
• nucleus typically U shaped
• histamine: potent vasodilator–increases diameter of BV (makes them leaky)
• increases inflammatory response
• much bigger than lymphocyte; granules obscure nucleus

Question 25

lymphocytes

Answer 25

• about 25%
• B and T cells of immunity
• smallest of all WBC; very little cytoplasm

Question 26

monocytes

Answer 26

• approx 5%
• called macrophages if in tissues
• largest of all with big nucleus

Question 27

Thyroid location

Answer 27

*overlies the trachea and inferior to the larynx

Question 28

Thyroid histology

Answer 28

• structure is colloid filled follicles

* follicle cells produce thyroid hormone in inactive form a& store in the colloid material

Question 29

parafollicular cells

Answer 29

*in the Thyroid

Question 30

parathyroid gland histology

Answer 30

more cellular

• chief cells
• oxyphil cells

Question 31

zona glomerulosa

Answer 31

• mineralcorticoids - ion balance

* controls minerals or ions

Question 32

zona fasciculata

Answer 32

• glucocorticoids-metabolic hormones

* help us make glucose to make ATP

Question 33

zona glomerulosa histology

Answer 33

*thinnest layer of the three (on top near the capsule)

Question 34

zona fasciculata histology

Answer 34

*thickest layer in histology

Question 35

zona reticularis histology

Answer 35

*less thick layer of the 3…closest to medulla

Question 36

zona reticularis

Answer 36

*mainly gonadocorticoids

Question 37

thymus

Answer 37

• mostly active when young

* decreases in size after puberty–pretty big in newborn